PROJECT SUMMARY/ABSTRACT Our long-term objective is to ascertain how protein conformation plays a role in biological function and in various diseases. Our specific aims are to treat the role of basic physical forces, key interactions, key residues, as well as the role of conformation, with an improved coarse-grained UNRES model, in several biological systems related to specific diseases. We will also continue the development of our UNRES model of nucleic acids (NARES-2P) and merge UNRES and NARES-2P into a viable package, which will be provided to the community. We will demonstrate how these aims can lead to valid predictions of structures and folding pathways of proteins, and protein-nucleic acid and protein-protein complexes. Our main focus will involve the application of this methodology to specific biological problems.